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|
package Monkey::Patch::Action::Handle;
use 5.010;
use strict;
use warnings;
use Scalar::Util qw(weaken);
use Sub::Delete;
our $VERSION = '0.04'; # VERSION
my %stacks;
sub __find_previous {
my ($stack, $code) = @_;
state $empty = sub {};
for my $i (1..$#$stack) {
if ($stack->[$i][1] == $code) {
return $stack->[$i-1][2] // $stack->[$i-1][1];
}
}
$empty;
}
sub new {
my ($class, %args) = @_;
my $type = $args{-type};
delete $args{-type};
my $code = $args{code};
my $name = "$args{package}::$args{subname}";
my $stack;
if (!$stacks{$name}) {
$stacks{$name} = [];
push @{$stacks{$name}}, [sub => \&$name] if defined(&$name);
}
$stack = $stacks{$name};
my $self = bless \%args, $class;
no strict 'refs';
no warnings 'redefine';
if ($type eq 'sub') {
push @$stack, [$type => $code];
*$name = $code;
} elsif ($type eq 'delete') {
$code = sub {};
$args{code} = $code;
push @$stack, [$type, $code];
delete_sub $name;
} elsif ($type eq 'wrap') {
weaken($self);
my $wrapper = sub {
my $ctx = {
package => $self->{package},
subname => $self->{subname},
extra => $self->{extra},
orig => __find_previous($stack, $self->{code}),
};
unshift @_, $ctx;
goto &{$self->{code}};
};
push @$stack, [$type => $code => $wrapper];
*$name = $wrapper;
}
$self;
}
sub DESTROY {
my $self = shift;
my $name = "$self->{package}::$self->{subname}";
my $stack = $stacks{$name};
my $code = $self->{code};
for my $i (0..$#$stack) {
if($stack->[$i][1] == $code) {
if ($stack->[$i+1]) {
# check conflict
if ($stack->[$i+1][0] eq 'wrap' &&
($i == 0 || $stack->[$i-1][0] eq 'delete')) {
my $p = $self->{patcher};
warn "Warning: unapplying patch to $name ".
"(applied in $p->[1]:$p->[2]) before a wrapping patch";
}
}
no strict 'refs';
if ($i == @$stack-1) {
if ($i) {
no warnings 'redefine';
if ($stack->[$i-1][0] eq 'delete') {
delete_sub $name;
} else {
*$name = $stack->[$i-1][2] // $stack->[$i-1][1];
}
} else {
delete_sub $name;
}
}
splice @$stack, $i, 1;
last;
}
}
}
1;
__END__
=pod
=head1 NAME
Monkey::Patch::Action::Handle
=head1 VERSION
version 0.04
=for Pod::Coverage .*
=head1 AUTHOR
Steven Haryanto <stevenharyanto@gmail.com>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Steven Haryanto.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
|
